Sparking plug.



UNITED STATES atented December 15, 1903.

CARL E. L. LIPMAN, OF BELOIT, WISCONSIN.

SPARKING PLUGn SPECIFICATION forming part of Letters Patent No. 746,968, dated December 1-5, 1903.

Application filed Tune 9, 1903. Serial No. 160,752. (No model() To all whom it may concern/.-

Be it known that LCARL E. L. LIPMAN, a citizen of the United States, residing at Belot, in the county of Rock and State of Wiscousin, have invented certain new and useful Improvements in Sparking Plugs, of which the following is a specification.

The object of this invention is to construct a sparking plug for explosive engines in which the end of the porcelain from which projects one point is kept clean bythe gases rushing past it at each compression and eX- plosion.

In the accompanying drawings, Figure 1 is an elevation of my improved sparking plug. Fig. 2 is a lengthwise central section.

The main portion comprises the screwthreaded ends 1 and 2, the center division 3, having an opening 4:, and the hexagonalA center section 5, by whichthe main portion can be turned.

The center portion 6 of the plug is cylindrical in cross-section and has an annular enlargement 7. This center portion is composed of porcelain orother suitable insulating material and has a longitudinal opening S, within which is located a metallic rod 9,having one end screw-threaded and its other end provided with an enlargement 10, from which projects a point 11. The enlargement is located in a cavity in the end of the center portion, so as to be flush therewith. A nut 12, turned on the screw-threaded end of the rod 9, clamps the rod in connection with the center portion. The opening 13 in the screwthreaded end 1 of the main portion is somewhat larger than the diameter of the center portion 6, so that an annular space is left aroundit. A thumb-nut 14 is located on the projecting screw-threaded end of the rod. A cap has ail-opening 15 in its end, being of a size to receive the center portion, and the central opening 16 of the cap is of a size to receive the annular enlargement 7 ot` the center portion. The lower end of the center portion 16 is internally screw-threaded.

In placing the parts of the plug together, packing 17 is placed between the end ot the cap and the annular enlargement, and packing 18 is placed between the annular enlargement and the ring 19. The center portion is then placed within` the opening 13 and the internal-screw-threaded lower end of the cap is turned in connection with the externalscrew-threaded end 1 of the main portion and turned down until the packings are sufticiently compressed to make a rigid connection. The ring 19 will rest upon the end ot the 'screw-threaded end of the main section, and when the parts are in the positions shown in the drawings the part 11 will be located within the opening 4 in the division-wall 3 the proper distance from the surface thereof to give the required spark. The end of the center portion 6 will stand free of the division-wall, leaving the space 20.

When the plug is in position in an explosive-engine, the opening 4: in the divisionwall will communicate with the interior of the cylinder, and when the gas is being compressed within the cylinder it will rush through the opening a past the point 11 and end of the center portion into the annular space around that section of the center portion within the opening 13, which will remove all soot from the point 11 and end ofthe center portion, thereby making it impossible to short-circuit the point with the metallic main portion ofthe plug. Each time a compression and an explosion takes place this cleaning process is carried on.

By the employment of the packings the parts can expand and contract without breaking or damaging them and at the same time make a tight joint, thereby preventing the escape of gases from the cylinder.

The cap is turned down by a Wrench placed on the hexagonal section 21, and the cap and center portion can be removed for an inspection of the point by uuscrewing the cap.

The packings around the center portion hold the center portion and cap together.

I claim as my invention- A sparking plug comprising a main portion constitutingl an electrode having both ends externally screw-threaded and provided with i2 Maese a lengthwise opening, a cap portion having a main portion and a second electrode carried screw-threaded connection with one end of bythe center section. the main portion, a center insulating-section having an annular enlargementlocated with- CARL E' L' LIPMAN' 5 in the cap portion, and packing placed be- Witnesses:

tweenl the enlargement and end of the cap, E. LIPMAN, and between the enlargement and end of F. F. LIVERMORE. 

